There is an increasing demand for lower power consumption in electronic apparatuses. As a result, large scale integration (LSI) circuits are provided with a power supply suspension function in an increasing number of cases. An LSI circuit having a power supply suspension function suspends power supply to unused circuit blocks among its internal circuit blocks to eliminate leak currents in these unused circuit blocks, thereby reducing power consumption. This function is preferable in portable communication apparatuses for which the demand for reduction of power consumption in a standby state is pressing.
[Patent Document 1] Japanese Patent Application Publication No. 2007-179345
[Patent Document 2] Japanese Patent Application Publication No. 2004-350058
[Patent Document 3] Japanese Patent Application Publication No. 2000-13215